165 will be pretty hard to run for a couple of those.
If you have not already done so I would overclock the CPU. That helps a lot more than most people think with WoW for one.
League is a bit weird. Last time I ran it I was running my 6700k at stock (4.2GHz) I got fps sometimes close to 500 but most of the time it was sitting around 150-200. So I don't really think you'll have trouble there and that's with the settings maxed. And with those being G-sync monitors should not be an issue.
As I recall (could be wrong) those monitors have a native 144Hz refresh and can overclock to 165Hz. I think you shouldrun it at 144Hz. In my experience that 21Hz is not goingto make a huge difference. It's barely noticeable (if at all)
The hard game to run will be WoW.
I had my 6700k @4.7GHz and would usually top out about 80-100 in Dalaran. Stormwind Trade District in busy times I would get like 55-75, and in raids, the worst being Nighthold, it would drop as low as 45.
In the world I run at 100Hz with sync so it caps out there, no idea how much higher it would go.
However, I did just put in an 8700k. Running at stock I lost about 10fps in Dalaran, haven't raided yet. But that's a 4.3GHz CPU, so you can see what a difference a few hundred MHz makes there. So anyways, I would OC that CPU for sure.
I haven't played Overwatch but that's probably your most graphics intensive game. From what I have seen you MAY (again I don't know for sure) need a slightly better GPU.
Heres a bench:
https://www.techspot.com/amp/review/1180-overwatch-benchmarks/page3.html
You can play with the settings but with that GPU it may be pretty hard to hit 144Hz there. It seems the CPU (should) be able to keep up there. Unfortunately I have not played overwatch so I don't know the exent of that.
That's similar with WoW. You may not be able to play with graphics too high up, but you should be able to get your GPU and CPU close.
I'll throw this in there:
At 1440p preset 7 and preset 10 are almost indistinguishable excpet for veiw distance and amount of ground clutter. And turn AA off, again it's not even really noticeable, and those will make the game MUCH easier to run. You could also scale back the environment sliders and turn down particle density for a little higher fps. Won't do much for raids but it helps a little there. I wouldn't turn particle density down lower than "good" I find it harder to raid at "fair"
For everything else the GPU should be fine.